1. Field of the Invention
The present invention relates to a computer readable recording medium in which, for example, programs for three-dimensional computer image processing are stored, a graduation rendering processing method, and a video game device.
2. Description of the Related Art
It has been suggested to carry out image processing for rendering defocused images in image processing of three-dimensional computer images that are used in a video game or the like. The defocused images can be obtained by providing an image rendered in a virtual three-dimensional space of a monitor screen with a graduation effect according to the depth of field and the like. A technique for giving the graduation effect according to the depth of field and the like is disclosed, for example, in Japanese Laid-Open Patent Nos. 139353/1994 and 222694/1998.
Japanese Laid-Open Patent No. 139353/1994 discloses an image processing technique for obtaining a defocused image by carrying out predetermined addition to and subtraction from a predetermined number of image data of adjacent pixels in accordance with input image data by means of a hardware configuration comprising flip-flop circuits.
In Japanese Laid-Open Patent No. 222694/1998, there is provided a graduation value buffer for storing information regarding the level of influence, which image data of each pixel of a frame buffer gives to the surrounding, as graduation values by the predetermined number of pixels. Moreover, a graduation image is generated by carrying out graduation filtering operation processing for image data of each pixel, which are read from the frame buffer, in accordance with the level of influence of the surrounding pixels read from the graduation value buffer. This technique is suitable, for example, for the generation of graduation images to obtain after-images of a moving image according to the traveling speed thereof.
The image processing technique shown in Japanese Laid-Open Patent No. 139353/1994 obtains defocused images by means of a hardware configuration comprising flip-flop circuits or the like. Accordingly, with this image processing technique, the addition and subtraction processing is in practice limited to pixels adjacent in the direction of principal scan, and it is difficult to obtain effective defocused images of multi-levels of halftone according to the depth of the virtual three-dimensional space.
The object of the present invention is to provide a computer readable recording medium in which programs for three-dimensional computer image processing are stored, a graduation rendering processing method, and a video game device, which obtains effective defocused (out-of-focus) images of multi-levels of halftone according to the depth of the virtual three-dimensional space without the necessity of complicated operation processing.
According to a first aspect of the present invention, a computer readable recording medium is characterized by having programs recorded thereon for allowing a computer to: set luminosity to a first three-dimensional image, that is, an original image so as to be greater in luminosity frontward in a depth of a virtual three-dimensional space and acquire a second three-dimensional image based on the first three-dimensional image with a luminosity which has been set. The computer also sets luminosity to the first three-dimensional image so as to be greater in luminosity backward in the depth of the virtual three-dimensional space and acquire a third three-dimensional image based on the first three-dimensional image with a luminosity which has been set. The computer also superimposes the second three-dimensional image on the third three-dimensional image with a positional relationship in which a center position of the third three-dimensional image having the luminosity which has been set is different from a center position of the second three-dimensional image, and displays the superimposed three-dimensional image.
In the first aspect of the present invention, the computer readable recording medium is characterized in that, in a case of superimposing the second three-dimensional image on the third three-dimensional image, the second three-dimensional image is superimposed on the third three-dimensional image with a positional relationship in which the third three-dimensional image is shifted by the unit of a pixel with respect to the second three-dimensional image.
In the first aspect of the present invention, the computer readable recording medium is characterized in that, in a case of superimposing the second three-dimensional image on the third three-dimensional image, the second three-dimensional image is superimposed on the third three-dimensional image with a positional relationship in which each of the third three-dimensional images is shifted by the unit of a pixel in n (n is a natural number) directions around the second three-dimensional image.
According to a second aspect of the present invention, a computer readable recording medium which is a recording medium is characterized by having programs recorded thereon for allowing a computer to: set luminosity to a first three-dimensional image, that is, an original image so as to be greater in luminosity backward in a depth of a virtual three-dimensional space and acquire a dummy three-dimensional image based on the first three-dimensional image with a luminosity which has been set; to superimpose the first three-dimensional image on the dummy three-dimensional image with a positional relationship in which a center position of the dummy three-dimensional image having the luminosity which has been set is different from a center position of the first three-dimensional image, and; to display the superimposed three-dimensional image.
In a third aspect of the present invention, a computer readable recording medium on which is recorded a three-dimensional computer image processing program for displaying an image on a virtual three-dimensional space of a monitor screen is characterized by having a program recorded thereon for allowing a computer to: carry out subtraction processing for reducing a luminosity of an original image of a frame buffer for screen display by a larger luminosity in an image located rearward in a depth of the virtual three-dimensional space. The computer also carries out addition processing for distributing and adding an image having a luminosity corresponding to a reduced value of luminosity in the subtraction processing around the original image of the frame buffer, with a position of the image shifted with respect to the original image. The computer also displays the image, which has been subjected to the subtraction processing and the addition processing, of the frame buffer on the screen.
In the third aspect of the present invention, the computer readable recording medium is characterized in that, in the addition processing, the image is displaced by the unit of a pixel in n directions (n is a natural number) to be distributed and added at n positions around the original image. Each of displaced images is provided with a 1/n luminosity corresponding to the reduced value of luminosity.
In the first to third aspects of the present invention, the computer readable recording medium is characterized in that, the depth of the virtual three-dimensional space is a distance in the direction of a visual axis between an imaginary plane, passing through a viewpoint and perpendicular to the visual axis, and the first three-dimensional image, that is, the original image.
According to a fourth aspect of the present invention, a graduation rendering processing method in three-dimensional computer image processing includes: setting luminosity to a first three-dimensional image, that is, an original image so as to be greater in luminosity frontward in a depth of a virtual three-dimensional space and acquiring a second three-dimensional image based on the first three-dimensional image with a luminosity which has been set. The computer also sets luminosity to the first three-dimensional image so as to be greater in luminosity backward in the depth of the virtual three-dimensional space and acquire a third three-dimensional image based on the first three-dimensional image with a luminosity which has been set. The computer also superimposes the second three-dimensional image on the third three-dimensional image with a positional relationship in which a center position of the third three-dimensional image having the luminosity which has been set is different from a center position of the second three-dimensional image, and displays the superimposed three-dimensional image.
In the fourth aspect of the present invention, the graduation rendering processing method in three-dimensional computer image processing is characterized in that, in a case of superimposing the second three-dimensional image on the third three-dimensional image, the second three-dimensional image is superimposed on the third three-dimensional image with a positional relationship in which the third three-dimensional image is shifted by the unit of a pixel with respect to the second three-dimensional image.
In the fourth aspect of the present invention, the graduation rendering processing method in three-dimensional computer image processing is characterized in that, in a case of superimposing the second three-dimensional image on the third three-dimensional image, the second three-dimensional image is superimposed on the third three-dimensional image with a positional relationship in which each of the third three-dimensional images is shifted by the unit of a pixel in n (n is a natural number) directions around the second three-dimensional image.
According to a fifth aspect of the present invention, a graduation rendering processing method in three-dimensional computer image processing includes: setting luminosity to a first three-dimensional image, that is, an original image so as to be greater in luminosity backward in a depth of a virtual three-dimensional space and acquiring a dummy three-dimensional image based on the first three-dimensional image with a luminosity which has been set. The method also includes superimposing the first three-dimensional image on the dummy three-dimensional image with a positional relationship in which a center position of the dummy three-dimensional image having the luminosity which has been set is different from a center position of the first three-dimensional image. The method further includes displaying the superimposed three-dimensional image.
According to a sixth aspect of the present invention, a graduation rendering processing method in three-dimensional computer image processing includes: carrying out subtraction processing for reducing a luminosity of an original image of a frame buffer for screen display by a larger luminosity in an image located rearward in a depth of the virtual three-dimensional space, and carrying out addition processing for distributing and adding an image having a luminosity corresponding to a reduced value of luminosity in the subtraction processing around the original image of the frame buffer, with a position of the image shifted with respect to the original image. The method also includes displaying the image, which has been subjected to the subtraction processing and the addition processing, of the frame buffer on the screen.
In the sixth aspect of the present invention, the graduation rendering processing method in three-dimensional computer image processing is characterized in that, in the addition processing, the image is displaced by the unit of a pixel in n directions (n is a natural number) to be distributed and added at n positions around the original image, and each displaced image is provided with a 1/n luminosity corresponding to the reduced value of luminosity.
In the first to sixth aspects of the present invention, the graduation rendering processing method in three-dimensional computer image processing is characterized in that the depth of the virtual three-dimensional space is a distance in the direction of a visual axis between an imaginary plane, passing through a viewpoint and perpendicular to the visual axis, and the first three-dimensional image, that is, the original image.
According to a seventh aspect of the present invention, a video game device for displaying backgrounds or game character images in a virtual three-dimensional space of a monitor screen includes a frame buffer for screen display. The device also includes a subtraction processor for reducing a luminosity of an original image of a frame buffer for screen display by a larger luminosity in an image located rearward in a depth of the virtual three-dimensional space. The device includes an addition processor for distributing and adding an image having a luminosity corresponding to a reduced value of luminosity in the subtraction processing around the original image of the frame buffer, with a position of the image shifted with respect to the original image. The device also includes a display that displays the image, which has been subjected to the subtraction processing and the addition processing, of the frame buffer on the screen.
According to an eighth aspect of the present invention, a video game device for displaying backgrounds or game character images in a virtual three-dimensional space of a monitor screen includes a second image acquiring system that sets luminosity to a first three-dimensional image, that is, an original image so as to be greater in luminosity frontward in a depth of a virtual three-dimensional space and acquires a second three-dimensional image based on the first three-dimensional image with a luminosity which has been set. The device also includes a third image acquiring system that sets luminosity to the first three-dimensional image so as to be greater in luminosity backward in the depth of the virtual three-dimensional space and acquires a third three-dimensional image based on the first three-dimensional image with a luminosity which has been set.
The device includes a superimposing system that superimposes the second three-dimensional image on the third three-dimensional image with a positional relationship in which a center position of the third three-dimensional image having the luminosity which has been set is different from a center position of the second three-dimensional image. The device also includes a display that displays the superimposed three-dimensional image.